old thumper jets

I'm getting ready to re-jet an 86 XL600R (dual carbs) at 1000 ft elev, but I'm not sure which series of Keihn mains and pilot to order.

Also, any opinions on kit versus ordering individual jets? The threads I've read say the dynojet kit doesn't come with a pilot jet, and a majority of the threads say to go with 64+ on the pilot jet.

My bike has the typical XL600R symptoms: Cough and die at idle or coasting, hard to start.


Any carb guys out there that can tell me which series jet are in the xl's keihn carbs? I'm guessing slot head KJ in the main? 21 or 22 series pilot? My service manual doesn't specify...

sorry,its been many years since ive had the carbs out of a xl600.

Man, you're up early. Its noon here in Germany....Thanks anyway

I live at1000 feet also. I have used XR carbs on my XL but I think the main difference is the removable main jet cover on the XR float bowl and the needles and jets. I recommend the XR needles and jet assemblies, 125-130 ,mains and 65 pilots. I also have had good results modifying the linkage and adjustments to get the secondary carb to open as soon as possible after the primary. I put 125 mains in both carbs for higher elevation and trail rides and 130 or 135 in the right side for lower elevations. I dont know what style jets they are but mains are hex headed, 6mm wrench removal.

Which model year XR carbs are you using?

I dont know what specific year they are, I think 85-87 are all very similar on the XR. They say PH52A A, on the right carb. I would guess 85 due to the A after the number? The parts listing shows all internals the same or superceded to same for those years. The odd thing about Xr carbs compared to XL is that they use a lot smaller slow jet, 40-48, and 45 is what is in my carbs. There must be some difference from XL internally to run that much smaller jet, opposed to 60-65 on the XL.

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